Fold "icmp pred (srem X, Y), Y" like we do for urem. Handle signed comparisons
in the urem case, though not the other way around. This is enough to get #3 from
PR9343!
llvm-svn: 126991
diff --git a/llvm/test/Transforms/InstCombine/icmp.ll b/llvm/test/Transforms/InstCombine/icmp.ll
index ff11bbf..fba2735 100644
--- a/llvm/test/Transforms/InstCombine/icmp.ll
+++ b/llvm/test/Transforms/InstCombine/icmp.ll
@@ -379,7 +379,7 @@
}
; PR9343 #1
-; CHECK: test39
+; CHECK: @test39
; CHECK %B = icmp eq i32 %X, 0
define i1 @test39(i32 %X, i32 %Y) {
%A = ashr exact i32 %X, %Y
@@ -387,10 +387,19 @@
ret i1 %B
}
-; CHECK: test40
+; CHECK: @test40
; CHECK: %B = icmp ne i32 %X, 0
define i1 @test40(i32 %X, i32 %Y) {
%A = lshr exact i32 %X, %Y
%B = icmp ne i32 %A, 0
ret i1 %B
}
+
+; PR9343 #3
+; CHECK: @test41
+; CHECK: ret i1 true
+define i1 @test41(i32 %X, i32 %Y) {
+ %A = urem i32 %X, %Y
+ %B = icmp ugt i32 %Y, %A
+ ret i1 %B
+}
diff --git a/llvm/test/Transforms/InstSimplify/compare.ll b/llvm/test/Transforms/InstSimplify/compare.ll
index 44c678c..11295b7 100644
--- a/llvm/test/Transforms/InstSimplify/compare.ll
+++ b/llvm/test/Transforms/InstSimplify/compare.ll
@@ -236,6 +236,15 @@
; CHECK: ret i1 %B
}
+define i1 @urem5(i16 %X, i32 %Y) {
+; CHECK: @urem5
+ %A = zext i16 %X to i32
+ %B = urem i32 %A, %Y
+ %C = icmp slt i32 %B, %Y
+ ret i1 %C
+; CHECK: ret i1 true
+}
+
define i1 @srem1(i32 %X) {
; CHECK: @srem1
%A = srem i32 %X, -5
@@ -244,6 +253,15 @@
; CHECK: ret i1 false
}
+define i1 @srem2(i32 %X, i32 %Y) {
+; CHECK: @srem2
+ %neg = sub i32 %Y, 0
+ %A = srem i32 %X, %Y
+ %B = icmp slt i32 %A, %neg
+ ret i1 %B
+; CHECK: ret i1 true
+}
+
define i1 @udiv1(i32 %X) {
; CHECK: @udiv1
%A = udiv i32 %X, 1000000